Efficiency Improvement in Rotary Compressor

This paper presents how we improved the efficiency in rotary compressor. At first, we made effort to estimate the power losses in the compressor, to analyze the operating conditions of the bearing and to calculate the performance of the compressor. Next, the temperature in housing and pressure in cylinder were measured in real compressors in order to obtain the data on the internal conditions of the compressor. As for the points which were insufficient in the measurement with a real compressor, model tests were also conducted using the test apparatus which simulated the conditions of leakage and lubrication in the real compressor. Then, on the basis of the analysis and the measurement above-mentioned, we evaluated the effects of various countermeasures to reduce losses. By employing the most effective counter-measures, we obtained a 12% increase in efficiency and minimized the decrease of efficiency when a capacity control device was in function.